This invention relates to an ink jet recording element. More particularly, this invention relates to an ink jet recording element containing a multiplicity of particles.
In a typical ink jet recording or printing system, ink droplets are ejected from a nozzle at high speed towards a recording element or medium to produce an image on the medium. The ink droplets, or recording liquid, generally comprise a recording agent, such as a dye or pigment, and a large amount of solvent. The solvent, or carrier liquid, typically is made up of water, an organic material such as a monohydric alcohol, a polyhydric alcohol or mixtures thereof.
An ink jet recording element typically comprises a support having on at least one surface thereof an ink-receiving or image-forming layer, and includes those intended for reflection viewing, which have an opaque support, and those intended for viewing by transmitted light, which have a transparent support.
It is well known that in order to achieve and maintain photographic-quality images on such an image-recording element, an inkjet recording element must:
Be readily wetted so there is no puddling, i.e., coalescence of adjacent ink dots, which leads to non-uniform density
Exhibit no image bleeding
Exhibit the ability to absorb high concentrations of ink and dry quickly to avoid elements blocking together when stacked against subsequent prints or other surfaces
Exhibit no discontinuities or defects due to interactions between the support and/or layer(s), such as cracking, repellencies, comb lines and the like
Not allow unabsorbed dyes to aggregate at the free surface causing dye crystallization, which results in bloom or bronzing effects in the imaged areas
Have an optimized image fastness to avoid fade from contact with water or radiation by daylight, tungsten light, or fluorescent light
An inkjet recording element that simultaneously provides an almost instantaneous ink dry time and good image quality is desirable. However, given the wide range of ink compositions and ink volumes that a recording element needs to accommodate, these requirements of ink jet recording media are difficult to achieve simultaneously.
Ink jet recording elements are known that employ porous or non-porous single layer or multilayer coatings that act as suitable image receiving layers on one or both sides of a porous or non-porous support. Recording elements that use non-porous coatings typically have good image quality but exhibit poor ink dry time. Recording elements that use porous coatings typically contain colloidal particulates and have poorer image quality but exhibit superior dry times.
While a wide variety of different types of porous image recording elements for use with ink jet printing are known, there are many unsolved problems in the art and many deficiencies in the known products which have severely limited their commercial usefulness. A major challenge in the design of a porous image-recording layer is to be able to obtain good quality, crack-free coatings with as little non-particulate matter as possible. If too much non-particulate matter is present, the image-recording layer will not be porous and will exhibit poor ink dry times.
EPA 813,978 A1 relates to an ink jet recording element wherein an ink absorption layer is used comprising fine particles, a hydrophilic binder and oil drops. However, there is a problem with this element in that the oil drops will migrate to the surface and cause changes in the appearance of the image.
U.S. Pat. No. 6,197,381 B1 relates to the production of a recording sheet from a coating composition comprising fine inorganic particles, a hydrophilic binder and a hydrophobic latex having a glass transition temperature of not more than 30xc2x0 C. However, there is a problem with this recording sheet in that it exhibits poor ink dry times.
Final Program and Proceedings of ISandT NIP14, pp. 150-152, relates to microporous paper having an image-receiving layer comprising inorganic core/organic shell particles. The organic shells are cationic polymers. However, there is no reference to the properties or identities of the cationic polymers.
It is an object of this invention to provide a porous ink jet recording element that has good coating quality, especially reduced cracking. It is another object of this invention to provide an ink jet recording element that exhibits good image quality, especially reduced coalescence, when printed.
These and other objects are achieved in accordance with the invention, which comprises an porous ink jet recording element comprising a support having thereon an image-receiving layer comprising:
(a) inorganic particles having a primary particle size of from about 7 to about 40 nm in diameter which may be aggregated up to about 500 nm;
(b) colloidal particles having a mean particle size of from about 20 to about 500 nm;
(c) water-insoluble, cationic, polymeric particles comprising at least about 20 mole percent of a cationic mordant moiety; and
(d) inorganic particles encapsulated with an organic polymer having a Tg of less than about 100xc2x0 C.
The porous inkjet recording element of the invention has good coating quality and image quality when printed.